At the end of his bestseller Literary Theory, the Marxist critic Terry Eagleton called for a back-to-basics approach to Eng lit teaching. What we needed, he said, was not some newfangled hybrid of Freudianism and formalism or feminism and phenomenology but a return to the study of rhetoric – of how "discourses are constructed in order to achieve certain effects". Nearly 30 years on, here comes Sam Leith's You Talkin' To Me?, an admirably slim volume that defines and analyses the craft of the great orators.

Leith's first task is to convince you that rhetoric is more than just the art of phoney baloney. The cover references such lingual luminaries as Boris Johnson and "Tricky Dicky" Nixon remind you of how often we use the word rhetoric in conjunction with the word "empty", but don't forget Churchill, says Leith. He was one of the 20th century's great rhetoricians – and there are those who believe that without the power of his oratory, our forebears might have been a lot more ready to let Hitler wreak his wreck.

I'm one of them, though I still think it's a shame that Leith's analysis of Hitler's own speechifying isn't as detailed as his discussion of Churchill. Amusing though it is to link the great dictator's hysterical guff about blood and soil with J-Lo begging her fans not to "be fooled by the rocks that I got/I'm still Jenny from the block", Leith never quite acknowledges the people-pleasing potency of Adolf's afflatus. (That's me using alliteration, by the way, one of many technical terms defined in Leith's marvellous glossary.)

Despite the fun I had reading it, I'm not sure who or what this book is for. Though it will help you understand what makes for a successful speech, it isn't really a primer in oratory. (Show me a best man who's worried about whether his speech has the requisite number of anapests and zeugmas and I'll show you someone unlikely to wow his audience.)

The truth is that unlike punctuation, which Lynne Truss made a small fortune out of with Eats Shoots & Leaves, or Latin, which Harry Mount did equally well from with Amo, Amas, Amat…, rhetoric isn't something many people regret not having worked at in school. And anyway, is working at it really going to improve your rhetoric? While the rules of punctuation and Latin can be learned by rote, rhetoric is rather less concrete. A talent for crafting finely balanced, rhythmic sentences is just that – a talent. And talent can't be taught.